Stabilization of glyceride oils



S. MUSHER STABILIZATION OF GLYCERIDE OILS Filed Oct. 9, 1939 looj, OIL OR FAT PARTICLES OF ANTIOXIDANT ANTI OXIDANT FILM OF EMULSFYING AGENT OlL GLOBULES on. nuLslF FILM ANTIOX IDANT INVENTOR fidne q%a sfier Y A ORNEY STABILIZED OIL OR FAT SUBSTANTIALLY OR LARGELY FREED OF ANTIOXIDANT OBTAINED BY BREAKING EMULSION OF FIG.3-

Patented Apr. 23, 194d nan i. HQ

rant 2,198,213 STABILKZA'EHON 01F GLYCERKDE E8 Sidney Muslier, New York, N. 322, assignor to Masher Foundation Incorporated, New York, N.Y., a corporation of New York Application October 9, 1939, Serial No. 298,642

6 Claims.

This invention relates to the stabilization of glyceride oils and particularly to the stabilization of oils released from an emulsified or dispersed phase as in the separation of oil from the 5 dispersed phase of an oil-in-water'dispersion.

It has not been found readily possible to add antioxidants or stabilizers directly to many types of glyceride oils, particularly when such antioxidants may not be oil soluble or miscible.

m It is a primary object of this invention therefore to retard the deterioration of substantially pureoils and particularly of pure glyceride oils and fats by the use of substantially oil insoluble antioxidants or antioxidants that. would normally Mi be ineffective or decreased in eiiectiveness when added to an oil and dissolved therein.

Further, it has been found that many antioxi dants have a substantially weakened action when added to pure oils or fats and only give such oils 3, and fats limited additional stability against rancidity and other forms of oxidative deterioration and it is among the further objects of the present invention to provide an improved method of stabilizing oils and fats and particularly glycreride oils and fats in which the antioxidants may be so utilized and combined with such oils and fats as to give them substantially greater stability and cause them to be substantially more resistant to the development of oxidative deteri- 30 oration and rancidity.

It has also been found that many antioxidant materials when added to or combined with an oil or fat in substantially pure form will leave materials in the oil or at which, although they in- 35 itially retard deterioration, nevertheless, after a substantial portion of time or after the oil or fat has stood, will aparently cause a more rapid deterioration or development of rancidity than would result if the pure oil or fat had been per- 6 mitted to stand or had been stored for the same length of time without any such addition.

It is, therefore, among the further objects of the present invention to provide a method of stabilizing substantially pure oils and fats in such all tioxidants may be utilized to the, fullestextent without at the same time introducing into the oil or fat agents or materials which will tend to counteract the antioxidants particularly after standing and which may even give rise after a a manner that the antioxygenic effect of the an-' pear from the more detailed description set forth below, it being understood, however, that this more detailed description is given by way of illustration and explanation only, and not by way of limitation, since various changes therein may 5 be made by those skilled in the art without departing from the scope and spirit of the present invention.

In accordance with this invention, I use desirably water soluble stabilizing materials for'addi- 10 tion to the aqueous phase of an oil containing aqueous composition and preferably a composition in which the oil occupies the dispersed phase and the water the continuous phase.

The oil or fat and particularly the glyceride oil or fat to which the present invention will be particularly directed, although not limited, may be dispersed or emulsified or otherwise combined with water and aqueous materials to permit of I the treatment according to the present applig cation, or in many cases the oil or fat may be used in naturally occurring dispersions of water rorm.

It has been found that under these conditions many water soluble materials exercise antioxygenic action when placed in the water phase and out of contact with the oil which they do not exercise when placed in the pure fat or oil itself.

Among the materials which may give little or greatly decreased antioxygenic effect when added to a pure oil or fat phase, particularly of a glyceride type, and which give a good effect when added to an aqueous phase without direct contact with the oil or fat are the crude sugars, including particularly crude cane and beet sugars.

Under these circumstances the water soluble stabilizing material is in the continuous aqueous phase and is not admixed in the dispersal oil or fat phase.

It is usually preferable at this point to heat the material containing the stabilizerat an elevated temperature in excess of F. and desirably in excess of F. or more.

Following the addition of the stabilizing ma- A5 terial thereto, the dispersion or emulsion is bro ken, whereby the oil or fat globules are coagulated and such oil or fat is released from the dispersion or emulsion. The oil globules are coagulated and the dispersion is broken by any means 50,

such as by the application of heat thereto, by centrifuging, rapid agitation, or similar means. Where the dispersion is broken and the oil or fat globules released by the use of heat, the previous elevated temperature treatment need not g5 have been applied. Where the dispersion is broken, however, by agitation, the heat is desirable for application priorto'the breaking of the dispersion.

The emulsifying material which serves in the aqueous dispersion to reduce or prevent contact between the dispersed fat or oil and the antioxidant material distributed in the aqueous phase, may be left in the final fat or oil or it'may be removed by suitable refining or processing from the final fat or oil which has been broken or segregated from the dispersion and in either case the fat or oil will have unusually high stability and resistance against the development of oxillii dative deterioration.

of the dispersion or emulsion,

Surprisingly, the oil or fat that is obtained following the breaking of the dispersion or emulsion is substantially free of the water soluble antioxygens added to the aqueous continuous phase but even though theoil or fat is free of the added antioxygenic material, such oil is nevertheless substantially stabilized against oxidative decomposition.

Surprisingly also, where the antioxygen is added to a pure fat or oil, its effectiveness is much less than where it is added to the aqueous continuous phase of an oil or fat in water dispersion or emulsion and the emulsion or preferably by a heat treatment, to release the oil and fat globules.

Among the water soluble antioxygenic materials that may be utilized are particularly the crude cane and beet sugars and their residues or mother liquors obtained during the commercial refining procedures, such residues including sorghum molasses, blackstrap molasses, etc.

The crude cane and beet sugar materials which may most desirably be utilized are those which are directly obtained by extraction from the cane 4a or beet, followed by evaporation to crystallized form without bleaching or char filtration and which contain in addition to a high carbohydrates Such water soluble carbohydrate materials are removed during the breaking of the emulsion or dispersion but will nevertheless serve to stabilize the fat or oil contained in the emulsion and when removed therefrom by the breaking of that emulsion or dispersion.

Although it is particularly desirable to use the substantially crude and unrefined cane and beet sugars, particularly in the case of the butterfat emulsion described in Example I given below, re-

possess 5 perature and then with the aqueous emulsion or in the dispersed dispersion broken to release the fat globule.

Ezrample I A butterfat emulsion containing 35% butterfat phase was treated by adding thereto 2.0% of refined sucrose in one case and 2.0% of crude unrefined crude cane sugar in another case. In each instance, the butterfat emulsion was then heated to 180 F. for 5 minutes and the emulsion was then broken by substantial dispersion then broken,

agitation so that the butterfat globules coalescl and rose to the surface of the container that w used for the beating operation. The butterfa that were thus obtained were compared in kee ing quality and it was observed that the butterf:

obtained from the emulsion to which the CIU( unrefined cane sugar had been added showed 1: fat the best keeping quality but at the same tirr the butterfat obtained from the emulsion 1 which had been added the refined cane sugar we somewhat better in keeping quality than the but terfat obtained from the emulsion to which n addition had been made. This was particular] surprising in view of the fact that when pur refined cane sugar is added to pure butterfat n improvement is observed, and even when crud cane sugar isadded to pure butterfat, the im provement in keeping quality is not comparabl to that obtained by adding the crude sugar t1 the emulsion and then breaking said emulsion a; described.

In addition to the use of the substantially crud( and unrefined cane and beet sugars and theii mother liquors, the alcoholic extracts obtained therefrom may also be utilized, such alcoholic extracts being obtained by dissolving, for example, one part by weight of the crude unrefined cane sugar in five parts by weight of ethyl alcohol, agitating at a slightly elevated temperature such as at about F. and filtering out the undissolved carbohydrate portion, evaporating the alcohol soluble portion preferably under reduced pressure to leave a substantially viscous and rather dark colored ethyl alcoholic extract of the crude cane sugar.

The application of breaking the emulsion heat is desirable before or dispersion or during the breaking of the emulsion or dispersion. Where heat is employed to break the emulsion or dispersion and Where such heat is preferably as high as F. and most preferably at F. or

higher, no additional heat need be given. The

heat that would be employed during the breakin of the emulsion is sufficient to give satisfactory antioxygenic protection, but at some stage during the operation heat should be employed.

These substances may be added to the emul-' sion or dispersion in an amount ranging from 0.005% to 3% oil contained in the emulsion or dispersion. Generally, it'is preferable to use less than 0.5% by weight of the antioxygenic material against the fat or oil weight contained in the emulsion or dispersion and such proportion will under normal circumstances give the'usual desirable improvement in keeping quality and stabilization of the oil or fat.

In any event, it is desirable for the emulsion to be subjected to an elevated temperature prior to the breaking of the emulsion in order for the desired stabilization to be effected. This stabilization occurs even where the fat globules are Subjected to substantial water; Washing in order to make sure that these water soluble materials are substantially removed during the water washing process.

For example, following the coaslescing of the butterfat globules, the butterfat may be washed with water using from 1 to 10 times the amount of water against the weight of the butterfat and the butterfat will nevertheless be substantially stabilized against oxidative deterioration.

Among other materials that can be utilized in a like manner are the glucamines including methyl glucamine, ethyl glucamine, etc. In ad against the weight of the fat or area-sis dition, the reaction products of sugar and ammonia may be prepared by merely adding the sugar to ammonia, permitting the sugar to react therewith and then recrystallizing the reaction product thereof. Such materials obtained being substantially water soluble and capable of addition direct to an emulsion or dispersion, which is then broken and which will serve to stabilize the fat or oil which has been coalesced or broken from the emulsion or dispersion to a much greater degree than would be obtained where the glucamine or the reaction product of ammonia and sugar were to be added direct to the oil or fat following the breaking of such emulsion or dispersion.

As indicated above, the application of heat at the time of the breaking of the emulsion or dispersion or prior to the breaking of such emulsion or dispersion is desirable.

It has been found most satisfactory, either before or during or after the segregation operation to subject the mixture of the fat and oil and the aqueous materials to a short elevated heat treatment, say at a temperature of above 212 F. and preferably 250 F. for a period varying from seconds to 2 or 3 minutes or more with the result that substantially greater stability isobtained in the final fat material.

In the wet or steam rendering of lard, oleo o'l, mutton grease, Neats foot oil, or other fats and including also the rendering of fish oil, fish liver oils, etc, such as oi cod liver oil, herring oil, mackerel oil, menhaden oil, whale oil, etc., the fat is in substantially aqueous suspension at the time of the rendering operation, such fat oc cupying the dispersed phase and the water occupying the aqueous continuous phase with the fish phospholipin and proteins serving asthe emulsifying colloids.

To the rendering lsettle as in the rendering of any one of the above materials may be added a relatively small amount, such as less than 3% of the substantiall crude sugars and after these materials have been added to the rendering hettle and the oil or fat emulsion or dispersion subjected to an elevated temperature preferably as high as 220 F. to 250 there will be obtained a very substantial increase in the stability of the oil or fat which is rendered by the breaking of the emulsion and the coalescing of the fat or oil globules.

, Example H In a similar manner, methyl glucamine was added to chopped hog fat which was then subjected to a steam rendering operation at 245 F. in which the fat of the hog or the lard became dispersed in the aqueous phase at the time of the steam rendering. Following the coalescing and release of the o l globules, the lard obtained was compared in stability with lard prepared from a similar lot of chopped hog fat and rendered similarly, such lard after rendering hav ing added to it 0.1% of methyl glucamine. It was observed that the lard which had been rendered in the presence of the-methyl glucamine and with the methyl glucamine occupying part of the aqueous continuous phase showed much superior keeping qualities as determined by subjecting the lard to test on the Swift Stability Apparatus than the lard which was rendered in the presence of the methyl glucamine and which after' rendering was substantially free of the methyl glucamine.

In the rendering procedure, the higher the prose may also be employed.

temperature at the time the oil is dispersed in the aqueous continuous phase in the presence of the substantially water soluble antioxygenlc material, the greater the stabilization or antioxygenic action exerted upon the oil.

For example, it seems desirable for the rendering to be conducted at temperature of about 220 F. to 250 F. or even higher and where the rendering is conducted at temperatures as high as 300 F. to 350 F. in the absence of these water soluble antioxygenic materials, even greater stabilization is obtained than where the lower temperatures are employed.

In addition to the use of the water soluble antioxygenic materials referred to, there may also desirably be employed for addition to the aqueous continuous phase of the oil in water emulsion or dispersion, combinations of materials "along with sugars, such as combinations of sugars with (a) phosphatides, phospholipins, phosphoric acid, or acid phosphates and (b) the polyhydroxy polycarboxy aliphatic acids such as tartaric acid, citric acid, maleic acid, etc.

In the case of a product such as lecithin which is substantially oil soluble, that product may be utilized in accordance with this invention for addition to the water phase so that its way into the dispersed oil or fat phase of the emulsion or dispersion byincorporating it in a major proportion of sugar, and preferably a finely powdered sugar, such as powdered sucrose or powdered dextrose, although granulated su For example, when soya lecithin is admixed thoroughly with 50% of powdered cane sugar, and preferably with 75% of powdered cane sugar, a satisfactory powdered product is obtained which will readily go into aqueous suspension or into the aqueous continuous phase of an oil in water emulsion or dispersion. Even a though lecithin is normally soluble in oil, never theless when it is prepared in this manner mixed with water soluble carriers, such as sugar, powdered skim mills, etc., it will be substantially soluble in the aqueous continuous phase.

Where combinations of sugar and. lecithin are employed, they are desirably first boiled in an aqeuous solution before being added to the emulsion containing an oil in the dispersed discontinuous phase. For example, a mixture may be prepared comprising equal parts dextrose and lecithin and this mixture may be added to 5 parts by'weight or" water to every 1 part of the dextrose lecithin combination and then heated to boiling in order to obtain a thorough mixture of the dextrose lecithin combina-- tion in the water which will produce a rather milky or cloudy solution. be added to the aqueous continuous phase of an oil in water emulsion and the dextrose lecithin combination will remain dispersed in the aqueous phase, nevertheless stabilizing the oil or fat discontinuous phase even after the emulsion has been broken and the oil or fat globules coalesced or released from the emulsion.

Example III it does not find by weight of v This solution may then 4 .To a butterfat emulsion similar to the emulsion described in Example I was added 0.3% by weight of an intimate mixture comprising powdered anhydrous dextrose and 30% soya lecithin in powdered form. After thorough admixture therein, the butterfat emulsion was heated to 175 F. for 10 minutes, cooled and then agitated to remove the butterfat. The butterfat bus obtained was very materially improved in eeping quality over butterfat similarly prepared ut without treatment with the dextrose-lecithin ombination at the elevated temperature.

In accordance with this invention, the antixidants described may be added to the aqueous base of an oil that is in the process of refining ich as in the process of causticating where large iantities ofmoisture are present and where the ritioxidant may be employed in the aqueous nase in the course of such refining process to ve protection to the fat phase. Following the ldition of the water soluble antioxidants to the zter phase in the course of the refining of such ls, such as of cottonseed oil, corn oil, soya bean l, etc., and following the breaking of the emul- )[1 or dispersion, the oil is released free of the ltioxidant but nevertheless stabilized against idative deterioration. in accordance with this invention an oil or fat my be placed into a dispersed or emulsified form, rated with the water soluble antioxygenic mate- VI and the emulsion or dispersion broken. Anier method is to start with an oil or fatwhich rmally occurs in its emulsified or dispersed ase and to treat that emulsion with the Water uble antioxygenic material. Then the emuln or dispersion may be treated at an elevated iperature to break the emulsion. in addition to the treatment of the glyceride or fats, mineral oils may similarly be treated stabilize them, as in the preparation of emul: as with the mineral oil in the dispersed phase 1 containing the antioxygenic material in the icons continuous phase. .his invention may also be employed in the 1m distillation of the essential oils, such as aniol, oil of orange, oil of lemon, etc. When antioxygenic water soluble material such as de cane or beet sugar as described above is ed to the aqueous continuous phase of the ;erial from which these various oils are disd by steam distillation, and where the temlture of distillation is at least at 150 :erably at 175 F. or higher, the oils will be itantially stabilized against oxidative deiration and materially improved in keeping ity. 1e process of the present invention is particly advantageous in that it eliminates from final oil or fat any objections of impurities or amination as might result from the antiants. While many antioxidants are objecible from the viewpoint of labeling, edibility, when the oil or fat is prepared in a conn substantially free of the antioxidants, apntly a much higher grade of oil or fat is ob- :d which'need not be labeled or contaminated. :hough this invention relates particularly to stabilization of glyceride oils that are red from the dispersed phase of an emulsion, rtheless it has also been observed that where vater soluble or water miscible antioxygens as the crude sugars or similar antioxygenic 1ct described are added to the aqueous conus phase of the emulsion containing the oil .t globules in the dispersed discontinuous and particularly where such emulsions are subjected to an elevated temperature such in excess of 170 F. and desirably in excess of F., even where the emulsion is not subntly broken and the oil is retained in the itinuous phase of the emulsion with the rygens present in the aqueous continuous reduce their F. and

water containing a small amount of a sugar as phase, the said dispersed oil or fat globules will be substantially stabilized against oxidative deterioration, although, in accordance with this invention, the oil or fat globules may desirably be coalesced and removed from the emulsified form. 6

In the drawing are shown diagrammatically four different specimens of materials for the purpose of illustrating the stabilization method of the present invention. Each of the Figs. 1 to 4 shows a vessel in diagrammatic transverse section which contains a solid, plastic or liquid material. In Fig. l in the vessel I0 is shown a 1 0% pure glyceride oil or fat which may be in refined condition which contains particels of an antioxidant. When antioxidants are added direct to a 100% pure oil or fat, the stabilization is not as thoroughly obtained as by the process of the present invention and it is usually necessary or desirable to remove the antioxidant from the oil or fat so as to eliminate the presence of foreign materials, to avoid contamination or decreased edibility, loss in flavor, or the development of micro-organisms. Even if the oil containing the antioxidant particles is dispersed in water as shown in Fig. 2 with the dispersed oil globules l3 being encircled or encased by an emulsifying film M, the fat or oil is not as effectively protected as by the present invention even though mostintimate contact with the antioxidant is obtained. With certain kinds of antioxidants particularly, the presence of water will greatly activity and efi'ectiveness.

In Fig. 3 the antioxidant particles are distributed in the water phase l5 and not in the oil "globules l3 and they are separated from the oil globules l3 by the emulsifying film II which p'revents contact or mixture between the water and the oil. In Fig. 4 is shown the stabilized oil or fat which may be obtained by breaking the emulsion or dispersion of Fig. 3, segregating the fat or 40 oil globules, and removing substantially all of the antioxidant I 2 with the water or aqueous phase, in spite of which a highly stabilized oilor fat is obtained.

By the expression animal glyceride oil is included both the glyceride oil obtained from meat as well as the glyceride .oil obtained from fish.

This application is a continuation in part of copending applications, Serial No. 260,898 filed March 10, 1939, and Serial No. 292,613 filed August 30, 1939, and through said applications continues the subject matter of application, 1 Serial No. 135,169 filed April 5, 1937.

Having described my invention, what I- claim is:

1. A process of stabilizing-glyceride oils and fats subject to oxidative deterioration against such deterioration which comprises adding a small amount of a mixture of an added sugar and an added phosphatide as an antioxidant to the aqueous continuous phase of a dispersion containing the oil and fat in the dispersed phase thGI'GOf RHd subjecting the 'dispersion to an elevated temperature of over 220 F., and then breaking the dispersion to obtain a stabilized oil, 65 substantially devoid of the antioxidant contained in the original aqueous continuous phase.

2. A process of producing a stabilized lard which comprises mixing together hog fat and an antioxidant, subjecting the mixture with agi- 7o tation to a temperature in excess of 220 F., and then removing the lard from the water containing the antioxidant, whergby a lard is produced which is substantially free of the antioxidant u masses and which is stabilized against oxidative deterioration.

3. A process of producing a stabilized animal glyceride oil which comprises mixing together animaPiat and water containing a sugar as an antioxidant, subjecting the mixture with agitation to a temperature in excess of, 220 F., and then removingthe oil from the water containing the antioxidant, whereby an oil is produced which is substantially free of the antiomdant and which is stabilized against oxidative deterioration.

d. A process of stabilizing a glyceride 011 subject to oxidative deterioration against such deterioration which comprises adding a small amount of a sugar as an antioxidant to the aqueous continuous phase of 'a glycerlde oil dispersion containing the glyceride oil in the disperse phase thereof, subjecting the dispersion to an elevated temperature of over 145 F., and then removing the glyceride oil which is in-a stabilized condition and which is substantially devoid of the antioxidant contained in the original aqueous continuous phase.

5. A processof stabilizing a glyceride all subiect to oxidative deterioration against such deterioration which comprises adding a small amount of a sugaras an antioxidant to the aqueous continuous phase of a food emulsion containing the glyceride oil in the disperse phase thereof, subjecting the emulsion to an elevated temperature of over 145 F., and then breaking the emulsion to obtain a stabilized glyceride oil, substantially devoid of the antioxidant contained in the original aqueous continuous phase.

6. A process of stabilizing a glyceride all subject to oxidative deterioration against web deterioration which comprises adding a small amount of a sugar and also a phosphatide as an antiigxidant to the aqueous continuous phase of a g ceride oil dispersion containing the glycerlde oil in the disperse phase thereof, subjecting the dispersion to an elevated temperature of over 145 EL, and then removing the glyceride oil which is in a stabilized condition and which is substan- .tially devoid of the antioxidant contained in the original aqueous continuous phase.

5mm manna. 

